from rest_framework import serializers
from goods.models import SKU



class CartSelectAllSerializer(serializers.Serializer):
    """购物车全选序列化器"""
    selected = serializers.BooleanField(label='全选')






class CartDeleteSerializer(serializers.Serializer):
    """删除购物车数据序列化器"""
    sku_id = serializers.IntegerField(label='商品ID', min_value=1)

    def validate_sku_id(self, value):
        try:
            sku = SKU.objects.get(id=value)
        except SKU.DoesNotExist:
            raise serializers.ValidationError('商品不存在')
        return value




class CartSKUSerializer(serializers.ModelSerializer):
    """
    购物车商品数据序列化器
    """
    count = serializers.IntegerField(label='商品数量')
    selected = serializers.BooleanField(label='是否勾选')

    class Meta:
        model = SKU
        fields = ('id', 'count', 'name', 'default_image_url', 'price', 'selected')


class CartSerializer(serializers.Serializer):
    """添加购物车序列化器"""

    sku_id = serializers.IntegerField(label='商品ID', min_value=1)
    count = serializers.IntegerField(label='商品数量', min_value=1)
    selected = serializers.BooleanField(label='是否勾选', default=True)

    def validate_sku_id(self, value):
        """对sku_id进行校验，判断其是否存在"""
        try:
            SKU.objects.get(id=value)
        except SKU.DoesNotExist:
            raise serializers.ValidationError('sku_id 不存在')
        return value